Assighob



E. W. LAWLER. v LINING FOR TUBE MILLS.

Patented Sept. 2, 1919.

2 SHEETS-SHEET 1.

l/VVENTOR 6 AW ZORNL-YS till EDWARD W. LAVTLER, F BAYONNE, NEW JERSEY, ASSIGNOR T0 HARDINGE CONICAL MILL GOIVIJPY, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

LlNIIiTG ron. rune-mats.

To all whom it may concern."

Be it known that l, EDWARD W. LAWLER, a citizen of the United States, residing at Bayonne, in the county of Hudson and State of New Jersey, have invented certain new and useful Improvements in inn ngs for Tube-Mills, of which the following isa full, clear, and exact description.

l'n grinding apparatus of the so-called tubemill type, in which the ore (or other material) is passed through a rotating drum, usually containing balls, pebbles or rods, the inner surface of the drum sufiers rapid wear, and it is therefore customary to provide the drum with a renewable llnlng to take the wear and thus protect the outer shell or body.v The lining can be fastened in place by various means, but considerable difficulty has heretofore been experienced in keeping the lining plates tight on the shell, especially after they have undergone any material amount of wear. llf the plates are bolted to the shell, which, is the simplest method, the boltheads wear oflquickly and the plates are then free.

It is accordingly the object of my present invention to provide an improved lining composed of plates and fastening devices which can undergo wear almost down to the shell itself without becoming detached. A

further object is to provide a lining of the kind mentioned,

in which any looseplates can be readily tightened from the outside,

thereby obviating the necessity ofemptying the drum. Another-object is to provide a lining in which the bolts or other devices by which the lining elements are secured to the shell are entirely covered or protected on the inside of the mill.- Another object is to pro vide alining in which vices will serve also to roughen the inner surface of the drum, thereby giving theias cending side of theidrum'greater lifting action. To these and other ends the invention consists in the novel features and combinations hereinafter described;

One formof the inventionds illustrated the accompanying drawings,.in. which- Figure l is a side view,partly in lo the fastening de Specification of Letters Patent. Patented Sept. 2, 1919 application filed December-.10, 1917. Serial No. 206,408.

tudinal section, of the barrel or drum of a conical mill.

Fig. 2 is a detail section on line 11-11 of Fig. 1, but on a much larger scale.

Fig. 3 is a perspective view of one of the lining elements, showing the recesses provided to receive the bolts or rivets by which the lining element is fastened to the shell.

Fig. 3 is a longitudinal sectional view showing the use of a bolt with a fiat head bearing on the side and end flanges of the recess.

Fig.- 4 is a sectional view similar to Fig. 2 but showing the invention applied to another type lining element.

, Fig. 5 is a perspective view of the preferred form of bolt used to fasten elements. 4

Fig. '6 is an under plan view of a lining element having a modified form of recess for the bolt head. N,

Fig. 7 is a perspective view of a bolt suitthe lining able for use with the recess illustrated in Fig. 6

The drumshown in Fig. 1 is of the now well known conical type, consisting, in the form shown, bases to a short cylindrical portion. At the endsof the axis are inlet and outlet trunof two cones connected at their nions 10, 11, on which the drum is supported for rotation.- My improved lining is designed particularly for but it can be used advantageously with cylindrical tubemills as well, containing balls, pebbles, rods or other grinding media.

The lining of the mill, in the embodiment illustrated in Figs. 1 "and 2, consists of a plurality of lining elements in the form of heavy metal plates, 12, usually iron or steel castings, curved to conform to the curvature of the barrel, a plurality of lining elements in the form of wedge-bars 13. In a conical mills of this type,

mill the plates are tapered, as indicated, and

are usually arranged in several circumferentlal courses, the number of courses and the circumferential width of the plates do endmg largely upon the size of the drum. erably the plates are arranged so as to break joints.

as V

The plates are secured in place by means of the wedge-bars 13, each a one-piece element, the sides of which are inclined to give the bar an outward taper, that is, outward relatively to the .drum, as clearly shown in Fig. 2. By reference the side edges of the plates 12 are correspondingly beveled, as shown at 14, to leave V-shaped spaces between them, into which the bars are fitted. The bars are provided with recesses 15, extending into the bars from one or both sideedges or both end-edges, as indicated in Fig. 3. The bolts are passed laterally into the recesses, which may be T-shaped for use with flat-headed bolts 16, 3, or flared to fit taper-headed bolts such as 16, Fig. 5.

If desired, the open portion of the recess, re-

maining after the bolt is in place, can be filled by means of a filler or filling block 17-, Fig. '2. The bolts project through suitably spaced holes in the shell 17 of the drum, so that the nuts can be readily set up from the outside. The fastening bars 13 preferably extend radially inward beyond the surface of the plates 12 and overlap the edges ofthe latter, as shown in Fig. 2. The bars thus constitute roughening bars, to aid in carrymg the ore or other material up with the ascendmg side of the drum as the latter ro-- tates about its longitudinal axis. The recesses 15 are short enough, measured radially of the drum, to be well below the inner surface of the plates 12, so that the entire lin- 1ng can suffer considerable wear without exposing the bolt-heads. 1

When the nuts on the outside of the drum are screwed up, the wedging bars are drawn down into the spaces between the lining plates, thereby exerting pressure on the plates 'both radially and laterally. The plates are thus bound together and held firmly upon the shell. It will also be seen that wear of the exposed surface of the lining cannot make the plates loose until the wear has reached a point where the boltheads are worn off. If the pounding, to WhlCll the drum is subjected in use, should cause the nuts to unscrew, thereby loosening the wedging bars and the plates, the same can be t1ghtened merely by settin up the nuts wlth an ordinary wrench. T e effects of the poundin are minimized by making the bolt-heads s orter than the recesses so as to leave a space above the bolts, as indicated at 12, Fig. 2, thereby avoiding direct transmission of blows from the bar to the bolts. liven when the parts are quite loose there 1s no danger of any of them falling out of I place, but small pieces of ore or pebble may get behind the plates or into the joints, and prevent the lining from fitting properly when the nuts are set up, unless the plates and wedgmg-bars are first taken out and the drum cleaned; The difliculty is readilyobviated by trying the nuts often enough to keep them tightly set up. Wedging-bars be tween the end-edges of the plates are, in general, unnecessary, especially in conical mills. The circumferential expansion of each course as its wedging-bars are drawn down toward the shell causes the course to bear firmly on the next larger course, and there is thus no tendency for any course to shift toward the apex of its cone.

In the embodiment shown in Fig. 1, all the lining elements are in the form of overlapping plates, 20, with bolt-recesses 15 in the thicker edges thereof. These recesses may also be provided with filling pieces like those shown at 17 Fig. 2.

In the form shown in Fig. 6 the recess in the lining element (in the present instance a wedge-bar) opens in the bottom of the bar in the form of a slot 21. The inner portion of the recess is enlarged, as indicated by the dotted line at 22. The bolt 23, Fig. 7,

has a fiat, elongated head 24:, which is passed into the slot and is then givena quarterturn to the position shown in. broken lines in Fig.6, the bolt-head then bearing against the angular shoulders or stops formed in the enlargement to prevent rotation of the bolt when the nut on the outside is set up.

To prevent leakage of water through the bolt-holes in the shell of the mill the recess 15 and filler 17 in the lining element may be provided with a rabbet or stuffing-box 25, as in Fig. 2, filled with a suitable packing 26, so that when the element is drawn down the packing will be compressed upon the shell around the. bolt.

It is to be understood that the invention is not limited to the exact construction herein described but can be embodied in other forms without departure from its spirit as defined by the appended claims.

I claim 1. In a grinding mill, the combination with a rotary drum, of a linin therefor having a plurality of longitudina ly extending members with edges provided with edge-recessesopening below the inner surface of said members, and bolts seated in said recesses and extending out through the wall of the drumfor securing said members thereto.

' neither 3. In a grinding mill the combination with a rota drum, of a ining therein comprising a p urality of plates arranged in circumferential series, outwardly tapering 5 Wedging bars between the plates and have ing recesses, Toolts seated! in the said recesses and extending out through the Wall of the drum for securing the wedging bars thereto and filling pieces fitting in and ciosin sai recesses, the holt heads being Whol y in- 10 closed in said recesses. K

' In. testimony whereof I hereunto afix my signature. v

EDWARD W. LAWLER. 

